package com.footinteraction;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;

import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;

/**
 * This class does all the work for setting up and managing Bluetooth
 * connections with other devices. It has a thread that listens for
 * incoming connections, a thread for connecting with a device, and a
 * thread for performing data transmissions when connected.
 */
public class BTCommService
{
	//private static final long serialVersionUID = 1L;

	// Debugging
	private static final boolean DebugView = true;
	private static final String TAG = "BTCommService";
    
    // Unique UUID for this application
    private static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
    
    // Member fields
    private final BluetoothAdapter	mAdapter;
    private final MainActivity	mActivity;
    private final Handler mHandler;
    
    private ConnectThread	mConnectThread;
    private ConnectedThread mConnectedThread;
    
    // Constants that indicate the current connection state
    private int mState;
    public final static int STATE_NONE = 0;       // we're doing nothing
    public final static int STATE_LISTEN = 1;     // now listening for incoming connections
    public final static int STATE_CONNECTING = 2; // now initiating an outgoing connection
    public final static int STATE_CONNECTED = 3;  // now connected to a remote device

    // Message types sent from the BluetoothChatService Handler
    public final static int MESSAGE_STATE_CHANGE = 1;
    public final static int MESSAGE_READ = 2;
    public final static int MESSAGE_WRITE = 3;
    public final static int MESSAGE_DEVICE_NAME = 4;
    public final static int MESSAGE_TOAST = 5;
    
    // Key names received from the BluetoothChatService Handler
    public final static String DEVICE_NAME = "device_name";
    public final static String TOAST = "toast";    
    
    /**
     * Constructor. Prepares a new BluetoothChat session.
     * @param context  The UI Activity Context
     * @param handler  A Handler to send messages back to the UI Activity
     */
    public BTCommService(Context context, Handler handler)
    {
    	mActivity = (MainActivity)context;
    	mHandler = handler;
        mAdapter = BluetoothAdapter.getDefaultAdapter();
        mState = STATE_NONE;       
    }

    /**
     * Set the current state of the chat connection
     * @param state  An integer defining the current connection state
     */
    private synchronized void setState(int state) 
    {
        if (DebugView) Log.d(TAG, "setState() " + mState + " -> " + state);
        mState = state;

        // Give the new state to the Handler so the UI Activity can update
        mHandler.obtainMessage(MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
    }

    /**
     * Return the current connection state. */
    public synchronized int getState() 
    {
        return mState;
    }

    /**
     * Start the chat service. 
     * Called by the Activity onResume() 
     */
    public synchronized void start() 
    {
        if (DebugView) Log.d(TAG, "start");

        // Cancel any thread attempting to make a connection
        if (mConnectThread != null) 
        {
        	mConnectThread.cancel(); 
        	mConnectThread = null;
        }

        // Cancel any thread currently running a connection
        if (mConnectedThread != null) 
        {
        	mConnectedThread.cancel(); 
        	mConnectedThread = null;
        }

        setState(STATE_LISTEN);
    }

    /**
     * Start the ConnectThread to initiate a connection to a remote device.
     * @param device  The BluetoothDevice to connect
     */
    public synchronized void connect( BluetoothDevice device ) 
    {
        if (DebugView) Log.d(TAG, "connect to: " + device);

        // Cancel any thread attempting to make a connection
        if (mState == STATE_CONNECTING) 
        {
            if (mConnectThread != null) 
            {
            	mConnectThread.cancel(); 
            	mConnectThread = null;
            }
        }

        // Cancel any thread currently running a connection
        if (mConnectedThread != null)
        {
        	mConnectedThread.cancel(); 
        	mConnectedThread = null;
        }

        // Start the thread to connect with the given device
        mConnectThread = new ConnectThread(device);
        mConnectThread.start();
        setState(STATE_CONNECTING);
    }

    /**
     * Start the ConnectedThread to begin managing a Bluetooth connection
     * @param socket  The BluetoothSocket on which the connection was made
     * @param device  The BluetoothDevice that has been connected
     */
    public synchronized void connected(BluetoothSocket socket, BluetoothDevice device) 
    {
        if (DebugView) Log.d(TAG, "connected");

        // Cancel the thread that completed the connection
        if (mConnectThread != null) 
        {
        	mConnectThread.cancel();
        	mConnectThread = null;
        }

        // Cancel any thread currently running a connection
        if (mConnectedThread != null) 
        {
        	mConnectedThread.cancel();
        	mConnectedThread = null;
        }

        
        // Start the thread to manage the connection and perform transmissions
        mConnectedThread = new ConnectedThread(socket);
        mConnectedThread.start();

        // Send the name of the connected device back to the UI Activity
        Message msg = mHandler.obtainMessage(MESSAGE_DEVICE_NAME);
        Bundle bundle = new Bundle();
        bundle.putString(DEVICE_NAME, device.getName());
        msg.setData(bundle);
        mHandler.sendMessage(msg);

        setState(STATE_CONNECTED);
    }

    /**
     * Stop all threads
     */
    public synchronized void stop()
    {
        if (DebugView) Log.d(TAG, "stop");
        
        if (mConnectThread != null)
        {
        	mConnectThread.cancel(); 
        	mConnectThread = null;
        }
        
        if (mConnectedThread != null) 
        {
        	mConnectedThread.cancel();
        	mConnectedThread = null;        	
    	}
        
        setState(STATE_NONE);
    }

    /**
     * Write to the ConnectedThread in an unsynchronized manner
     * @param out The bytes to write
     * @see ConnectedThread#write(byte[])
     */
    public void write(byte[] out) 
    {
        // Create temporary object
        ConnectedThread r;
        // Synchronize a copy of the ConnectedThread
        
        synchronized (this) 
        {
            if ( mState != STATE_CONNECTED )
            	return;
            
            r = mConnectedThread;
        }
        
        // Perform the write unsynchronized
        r.write(out);
    }

    /**
     * Indicate that the connection attempt failed and notify the UI Activity.
     */
    private void connectionFailed() 
    {
    	setState(STATE_LISTEN);

        // Send a failure message back to the Activity
        Message msg = mHandler.obtainMessage(MESSAGE_TOAST);
        Bundle bundle = new Bundle();
        bundle.putString(TOAST, "Unable to connect device");
        msg.setData(bundle);
        mHandler.sendMessage(msg);
    }

    /**
     * Indicate that the connection was lost and notify the UI Activity.
     */
    private void connectionLost() 
    {
        setState(STATE_LISTEN);

        // Send a failure message back to the Activity
        Message msg = mHandler.obtainMessage(MESSAGE_TOAST);
        
        Bundle bundle = new Bundle();
        bundle.putString(TOAST, "Device connection was lost");
        
        msg.setData(bundle);
        
        mHandler.sendMessage(msg);
    }

    /**
     * This thread runs while attempting to make an outgoing connection
     * with a device. It runs straight through; the connection either
     * succeeds or fails.
     */
    private class ConnectThread extends Thread 
    {
        private final BluetoothSocket mmSocket;
        private final BluetoothDevice mmDevice;

        public ConnectThread(BluetoothDevice device) 
        {
            mmDevice = device;
            BluetoothSocket tmp = null;

            // Get a BluetoothSocket for a connection with the
            // given BluetoothDevice
            try 
            {
                tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
            }
            catch (IOException e) 
            {
                Log.e(TAG, "create() failed", e);
            }
            mmSocket = tmp;
            
            this.setName("ConnectThread");
        }

        public void run() 
        {
            Log.i(TAG, "BEGIN mConnectThread");
            setName("ConnectThread");

            // Always cancel discovery because it will slow down a connection
            mAdapter.cancelDiscovery();

            // Make a connection to the BluetoothSocket
            try 
            {
                // This is a blocking call and will only return on a
                // successful connection or an exception
                mmSocket.connect();
            }
            catch (IOException e) 
            {
                connectionFailed();
                
                // Close the socket
                try 
                {
                    mmSocket.close();
                } 
                catch (IOException e2) 
                {
                    Log.e(TAG, "unable to close() socket during connection failure", e2);
                }
                
                // Start the service over to restart listening mode
                BTCommService.this.start();
                
                return;
            }

            // Reset the ConnectThread because we're done
            synchronized (BTCommService.this) 
            {
                mConnectThread = null;
            }

            // Start the connected thread
            connected(mmSocket, mmDevice);
        }

        public void cancel() 
        {
            try 
            {
                mmSocket.close();
            }
            catch (IOException e) 
            {
                Log.e(TAG, "close() of connect socket failed", e);
            }
        }
    }
    

    /**
     * This thread runs during a connection with a remote device.
     * It handles all incoming and outgoing transmissions.
     */
    private class ConnectedThread extends Thread 
    {
        private final BluetoothSocket mmSocket;
        private final InputStream mmInStream;
        private final OutputStream mmOutStream;

        public ConnectedThread(BluetoothSocket socket) 
        {
            Log.d(TAG, "create ConnectedThread");
            mmSocket = socket;
            InputStream tmpIn = null;
            OutputStream tmpOut = null;

            // Get the BluetoothSocket input and output streams
            try 
            {
                tmpIn = socket.getInputStream();
                tmpOut = socket.getOutputStream();
            }
            catch (IOException e) 
            {
                Log.e(TAG, "temp sockets not created", e);
            }
            
            mmInStream = tmpIn;
            mmOutStream = tmpOut;
            
            this.setName("ConnectedThread");
            this.setPriority(NORM_PRIORITY);
        }

        public void run() 
        {
            Log.i(TAG, "BEGIN mConnectedThread");
            
            byte[] reading_buffer = new byte[2048];
            int bytes;
            
            // Keep listening to the InputStream while connected
            while ( true ) 
			{
				try 
				{
					// Read from the InputStream
					if( mmInStream.available() > 0 )
					{	
						bytes = mmInStream.read(reading_buffer, mActivity.index, (reading_buffer.length - mActivity.index));
											
			    		// Send the obtained bytes to the UI Activity
						// 
						// !! caution
						// if it use message method, data will broken. 
						//
						mActivity.OnReceive(reading_buffer, bytes + mActivity.index);
					}
				}
				catch (IOException e) 
				{
					Log.e(TAG, "disconnected", e);
				    connectionLost();
				    break;
				}
			}
        }

        /**
         * Write to the connected OutStream.
         * @param buffer  The bytes to write
         */
        public void write(byte[] buffer) 
        {
            try 
            {
                mmOutStream.write(buffer);

                // Share the sent message back to the UI Activity
                mHandler.obtainMessage(MESSAGE_WRITE, -1, -1, buffer).sendToTarget();
            }
            catch (IOException e) 
            {
                Log.e(TAG, "Exception during write", e);
            }
        }

        public void cancel() 
        {
            try 
            {
                mmSocket.close();
            }
            catch (IOException e) 
            {
                Log.e(TAG, "close() of connect socket failed", e);
            }
        }
    }
}